Django在管理中完成操作时发出两次信号

Question

我有一个简单的信号，当对象被删除时就会启动

@receiver(post_delete, sender=Operation, dispatch_uid="delete_operation")
def delete_operation(sender, instance, **kwargs):
    # Track balance operations for delete
    instance.user.balance = instance.user.balance - int(instance.amount) # Note the "-"
    instance.user.save()

当我的平衡是错误的时候，两次启动平衡信号。我想避免2次触发。我搜索了stackoverflow并尝试了几种解决方案，但仍然没有成功。在

以下是如何导入信号：

在应用程序.py在

^{pr2}$

如果有人有主意的话，欢迎！！在

Answer 1

@receiver(post_delete, sender=Operation, dispatch_uid="delete_operation")
def delete_operation(sender, instance, action, **kwargs):
    if action[0:4] == 'post':
        # Track balance operations for delete
        instance.user.balance = instance.user.balance - int(instance.amount) # Note the "-"
        instance.user.save()

每个信号有两个动作：前实例和后实例在更改前有字段，后实例在更改后有字段。在

• 前加和后加
• 移除前和移除后